Claude Fable 5.1 (High, Default Fallback) vs Claude Opus 5 (Medium)
Which is better for the money: Claude Fable 5.1 (High, Default Fallback) by Anthropic or Claude Opus 5 (Medium) by Anthropic? Intelligence, total benchmark cost, and end-to-end time from Artificial Analysis & other sources, snapshot 2026-10-24.
Trade-off
Verdict
Depends on your budget
Claude Fable 5.1 (High, Default Fallbac… scores 6.4 points higher (51.2 vs 44.8) but costs 1.9× as much to run the benchmark ($5242 vs $2732; both flagship class). Pick Claude Fable 5.1 (High, Default Fallbac… when the extra intelligence is worth the premium, otherwise Claude Opus 5 (Medium).
| Metric | Claude Fable 5.1 (High, Default Fallback) | Claude Opus 5 (Medium) | Difference |
|---|---|---|---|
| Intelligence (higher is better) | 51.2 | 44.8 | −12.5% Claude Opus 5 (Medium) is 12.5% less intelligent |
| Total AA cost (lower is better) | $5,241.59 | $2,731.91 | −47.9% Claude Opus 5 (Medium) is 47.9% cheaper |
| End-to-end time (lower is better) | 34.32s | 13.14s | −61.7% Claude Opus 5 (Medium) is 61.7% faster |
| Price per 1M tokens (in / out) | $10.0 / $50.0 | $5.00 / $25.0 | |
| Input modalities | Text, Image | Text, Image |
Claude Opus 5 (Medium) vs Claude Fable 5.1 (High, Default Fallback): 12.5% less intelligence, 47.9% less cost to run the AA benchmark, and 61.7% faster end-to-end.
Today's Pareto frontier
Against the frontier
- Claude Fable 5.1 (High, Default Fallback) is off the frontier: at the same or lower cost, Claude Opus 5.5 (Xhigh, Default Fallback) scores 56.00 for $4057.
- Claude Opus 5 (Medium) is off the frontier: at the same or lower cost, Claude Opus 5.5 (High, Default Fallback) scores 53.60 for $2172.
Claude Fable 5.1 (High, Default Fallback)Claude Opus 5 (Medium)Today's Pareto frontierEvery other model
Matchup
Compare something else
Agents:
Accept: text/markdown or ?format=md returns this page as Markdown. JSON: /api/v1/compare/claude-fable-5-1-high/claude-opus-5-medium · Markdown: /api/v1/compare/claude-fable-5-1-high/claude-opus-5-medium?format=md · llms.txt · agent skill